Countess Stephanie Wurmbrand-von Stuppach was a Hungarian pianist, composer and writer. In 2019 a book was published about her for the first time. Unfortunately – for me at least ;-) – it is in Slovak, but there is a German abstract of the book that runs to 8 pages (I am happy to provide a copy to anybody who is interested, please PM me). Her Wikipedia entry (https://en.wikipedia.org/wiki/Stephanie_Wurmbrand-Stuppach) is rather short but does give quite a detailed work list.
As for actually hearing her music, the only piece I have been able to find is this piece from her piano cycle op. 33 'Die schöne Melusine' in two recordings on Youtube:
https://youtu.be/kD6hKTCOqfs
https://youtu.be/Fy5TE3q8U1w
Most of her works appear to have survived, though, so more recordings may become available at some time in the future.